Electron tube socket

ABSTRACT

This invention relates to an electron tube socket. Said electron tube socket comprises an insulating base formed therein with a plurality of pin inserting openings arranged on a circle and disposed equidistantly from one another and with an annular groove disposed on the upper surface of the insulating base, said insulating base futher being formed with a plurality of recesses extending downwardly from said annular groove to the underside of the insulating base, a plurality of terminal contacts each comprising a pin holding cylindrical stem and a terminal portion formed integrally with each other, each of said plurality of terminal contacts having its pin holding cylindrical stem being received in one of said pin inserting openings and said terminal portion facing one of said plurality of recesses beneath the insulating base, and a conducting ring secured in said annular groove in said insulating base and formed integrally with a plurality of projections each adapted to be received in one of said plurality of recesses and disposed in spaced apart juxtaposed relationship to the terminal portion of one of said plurality of terminal contacts so as to form an arc-over gap therebetween.

United States Patent [191 Suzuki Apr. 16, 1974 ELECTRON TUBE SOCKET [7 51 Inventor: Minoru Suzuki, Tokyo, Japan [7 3] Assignee: Showa Musen Kogyo Kabushiki Kaisha, Tokyo, Japan [22] Filed: Mar. 19, 1973 [21] Appl. No.: 342,630

[30] Foreign Application Priority Data Apr. 19, 1972 Japan 47-46531 [52] US. Cl 313/318, 313/325, 339/193 VS [51] Int. Cl. H0lj 5/50 [58] Field of Search 313/313, 318, 325;

[56} References Cited UNITED STATES PATENTS 3,377,612 4/1968 Klier et al. 3l3/325 3,466,492 9/1969 Crellin 313/325 3,543,220 11/1970 Jones 338/193 VS Primary Examiner-Archie R. Borchelt Assistant Examiner-Wm. H. Punter Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher ABSTRACT This invention relates to an electron tube socket. Said electron tube socket comprises an insulating base formed therein with a plurality of pin inserting openings arranged on a circle and disposed equidistantly from one another and with an annular groove disposed on the upper surface of the insulating base, said insulating base futher being formed with a plurality of recesses extending downwardly from said annular groove to the underside of the insulating base, a plurality of terminal contacts each comprising a pin holding cylindrical stern and a terminal portion formed integrally with each other, each of said plurality of terminal contacts having its pin holding cylindrical stem being received in one of said pin inserting openings and said terminal portion facing one of said plurality of recesses beneath the insulating base, and a conducting ring secured in said annular groove in said insulating base and formed integrally with a plurality of projections each adapted to be received in one of said plurality of recesses and disposed in spaced apart juxtaposed relationship to the terminal portion of one of said plurality of terminal contacts so as to form an arcover gap therebetween.

4 Claims, 6 Drawing Figures PATENTEDAPR is 19m sum 1 0r 2 FIG. I

PRIOR ART PATENTED PR 16 I914 SHEET 2 [IF 2 ELECTRON TUBE SOCKET This invention relates to an electron tube socket, such for example as a cathode ray tube.

A high voltage of 20 to 25 KV is impressed on an anode of a cathode ray tube or other electron tube. The high voltage often caused a focus screen grind to be exposed to a discharge from the anode, thereby causing damage to the circuits involved.

In one type of electron tube sockets known in the art, contact pins 3 projecting from a base 2 of an electron tube 1 are inserted in cylindrical terminal contacts of the socket 4 so that the contact pins 3 may be connected to the contacts 5 as shown in FIG. 1. There are provided arresters 6 which are disposed between the ground and the contacts 5 with a predetermined arcover gap therebetween. When an abnormally high voltage is produced in the electrode, a high voltage current produced by the discharge is passed to the ground through the arresters 6 to provide protection for the circuits.

In the case of cathode ray tubes for color television receivers, four to arresters 6 are required. Since the arresters 6 are parts formed separately from the socket 4, the use of such arresters requires the operation of connecting them to the socket and consequently increases production cost.

An object of this invention is to provide a socket of the type described in which the arresters are formed integrally with the socket.

Another object of the invention is to provide a socket of the type described which is easy and ready to assemble.

Another object of the invention is to provide a socket of the type described which permits the arc-over gap to be correctly adjusted in the socket.

Still another object of the invention is to provide a socket of the type described which is small in size and which produces no discharge between the adjacent terminal contacts even if a number of terminal contacts are arranged in side-by-side relationship.

A further object of the invention is to provide a socket of the type described which is low in cost.

Additional and other objects as well as features and advantages of the invention will become evident from the description set forth hereinafter when considered in conjunction with the accompanying drawings, in which:

FIG. 1 is a side view, with certain partsbeing cut away, of a socket of the prior art having an electron tube mounted thereon and connected to arresters for grounding a high voltage current produced at the time of discharge;

FIG. 2 is a plan view of one embodiment of the socket according to the invention;

FIG. 3 is an exploded perspective view of the socket of FIG. 2;

FIG. 4 is a sectional view taken along the line A-A of FIG. 2;

FIG. 5 is a sectional view taken along the line BB of FIG. 2; and

FIG. 6 is a sectional view taken along the line C-C of FIG. 2.

In FIG. 2 to FIG. 6, 10 generally designates a socket which comprises, as best shown in FIG. 3, an annular insulating plate 11, a conducting ring 12, an insulating base 13, terminal contacts 14 only one of such contacts is shown in FIG. 3 and an insulating plate 15. The insulating base 13, which is in discal form and made of a synthetic resinous material, has a center axial bore 16 extending vertically therethrough. The insulating base 13 is formed in its central upper portion with an annular projection 17 which is formed therein with a plurality of pin inserting openings 18, 14 in number in the case of cathode ray tube sockets for color television receivers, for example, which are disposed equidistantly from one another.

An annular groove 19 of a small width is formed on the upper surface of the insulating base 13 while a plurality of radially disposed grooves 21 of a small depth are formed on the underside thereof each of which communicates with one of the pin inserting openings 18. The grooves 21 are separated from the center axial bore 16 by a wall 20 of a small thickness and open on the outer periphery of the insulating base 13.

Formed between the radial grooves 21 and the annular groove 19 are recesses 23 extending from the annular groove 19 to the radial grooves 21 so as to receive therein projections 22 formed in the conducting ring 12. Ribs 24 for keeping the conducting ring 12 in position are formed on opposite wall surfaces of the annular groove 19 and each disposed between the adjacent recesses 23.

The terminal portions 25 of those terminal contacts 14 which are connected to an anode on which a high voltage is impressed are disposed at the side of one portion of the insulating base 13. -Two shielding walls 26 are disposed adjacent such one portion of the insulating base 13 to extend radially outwardly of the socket 10. Four opening 27 are formed in the insulating base 13 and disposed outwardly of the annular groove 19 for receiving pins therein to fasten the parts together.

The conducting ring 12 is formed by bending a sheet metal in annular form so as to be fitted in the annular groove 19 in the insulating base 13. The projections 22 each adapted to extend into one of the recesses 23 are formed on the underside of the ring and disposed equidistantly from one another. The projections 22, which are rounded at their lower ends, may have any length as desired. A terminal member 28 is formed integrally with the ring 12 and extends outwardly therefrom.

The annular insulating plate 11 which has the same outer diameter as the insulating base 13 defines an opening 29 for receiving the annular projection 17 therein and has in one portion thereof a cutout for receiving the shielding walls 26 therein. Four openings 30 aligned with the openings 27 are formed in the annular insulating plate 11.

The terminal contacts 14 each comprises a pin receiving cylindrical stem 31 and the terminal portion 25. The stem 31 is formed by bending a conducting sheet in cylindrical form so that it may be received in one of the pin inserting openings 18. The stem 31 is narrowed in one portion thereof so that it may tightly receive therein a contact pin. The terminal portion 25 of a plate shape having a small width is formed integrally with the stem 31 and extends at right angles to the stem 31. The terminal portion 25 is bent downwardly at a portion thereof, so that the terminal portion 25 is received in one of the radial grooves 21 and extends outwardly through the open end of the groove 21 at the outer periphery of the insulating base 13.

The insulating plate 15 which is discal in shape has the same outer diameter as the insulating base 13 and an inner diameter which is substantially equal to the diameter of the axial center bore 16. The discal insulating plate is cut out in one portion thereof for receiving the shielding walls 26 therein, and formed on its upper surface with a plurality of radially disposed ribs 32 each adapted to be received in one of the radial grooves 21 for holding the terminal portions 25 of the terminal contacts 14 between the insulating plate 15 and the in sulating base 13. Four openings 33'aligned with the openings 27 are formed in the outer marginal portion of the insulating plate 15.

The manner in which the parts of the socket described above are assembled into a complete product will now be described. The pin receiving stems 31 of the terminal contacts 14 are inserted from below in the pin receiving openings 18 formed in the insulating base 13, so that the terminal portions 25 are disposed in the radial grooves 21. Then the radial ribs 32 formed on the upper surface of the insulating plate 15 are fitted in the radial grooves 21, so that the terminal portions 25 are held in place between the insulating base 13 and insulating plate 15.

Thereafter, the conducting ring 12 is fitted in the annular groove 19 on the upper surface of the insulating base l3,'and the projections 22 thereof are inserted in the recesses 23, so that the front end of each projection 22 is disposed in spaced juxtaposed relationship to the terminal portion 25 of each terminal contact 14. The annular insulating plate 11 is mounted on the insulating base 13 so that the annular projection 17 may be fitted in the opening 29 defined by the annular insulating plate 11 to bring the openings 30, 27 and 33 into alignment with one another and inserting clamp pins 34 therein as shown in FIG. 5 so as to fasten the parts together as a unit.

By assembling the parts as aforementioned, a predetermined arc-over gap G can be formed between the terminal portion 25 of each terminal contact 14 and each projection 22 of the conducting ring 12. The terminal contacts 14 are completely isolated from one another, so that a discharge between them can be prevented.

What is claimed is:

1. An electron tube socket comprising an insulating base formed therein with a plurality of pin inserting openings arranged on a circle and disposed equidistantly from one another and with an annular groove disposed on the upper surface of the insulating base, said insulating base further being formed with a plurality of recesses extending downwardly from said annular groove to the underside of the insulating base, a plurality of terminal contacts each comprising a pin holding cylindrical stem and a terminal portion formed inte grally with each other, each of said plurality of terminal contacts having its pin holding cylindrical stem being received in one of said pin inserting openings and said terminal portion facing one of said plurality of recesses beneath the insulating base, and a conducting ring secured in said annular groove in said insulating base and formed integrally with a plurality of projections each adapted to be received in one of said plurality of recesses and disposed in spaced apart juxtaposed relationship to the terminal portion of one of said plurality of terminal contacts so as to form an arc-over gap therebetween.

2. An electron tube socket according to claim 1 further comprising an insulating plate mounted on the upper surface of said insulating base for fixing the conducting ring, and another insulating plate mounted on the underside of said insulating base for fixing said plurality of terminal contacts, said two insulating plates and said insulating base each being formed therein with a plurality of openings aligned with one another so as to receive therein pins for clamping the elements together as a unit.

3. An electron tube socket according to claim 1 wherein said annular groove formed in said insulating base is formed on its inner wall surface with a plurality of ribs for firmly holding the conducting ring in position in said annular groove.

4. An electron tube socket according to claim 1 wherein said insulating base is formed on its underside with a plurality of radial grooves each communicating with one of said plurality of pin inserting openings and one of said recesses corresponding in position to said one pin inserting opening, said terminal portion of each said terminal contact being disposed in one of said plurality of radial grooves. 

1. An electron tube socket comprising an insulating base formed therein with a plurality of pin inserting openings arranged on a circle and disposed equidistantly from one another and with an annular groove disposed on the upper surface of the insulating base, said insulating base further being formed with a plurality of recesses extending downwardly from said annular groove to the underside of the insulating base, a plurality of terminal contacts each comprising a pin holding cylindrical stem and a terminal portion formed integrally with each other, each of said plurality of terminal contacts having its pin holding cylindrical stem being received in one of said pin inserting openings and said terminal portion facing one of said plurality of recesses beneath the insulating base, and a conducting ring secured in said annular groove in said insulating base and formed integrally with a plurality of projections each adapted to be received in one of said plurality of recesses and disposed in spaced apart juxtaposed relationship to the terminal portion of one of said plurality of terminal contacts so as to form an arc-over gap therebetween.
 2. An electron tube socket according to claim 1 further comprising an insulating plate mounted on the upper surface of said insulating base for fixing the conducting ring, and another insulating plate mounted on the underside of said insulating base for fixing said plurality of terminal contacts, said two insulating plates and said insulating base each being fOrmed therein with a plurality of openings aligned with one another so as to receive therein pins for clamping the elements together as a unit.
 3. An electron tube socket according to claim 1 wherein said annular groove formed in said insulating base is formed on its inner wall surface with a plurality of ribs for firmly holding the conducting ring in position in said annular groove.
 4. An electron tube socket according to claim 1 wherein said insulating base is formed on its underside with a plurality of radial grooves each communicating with one of said plurality of pin inserting openings and one of said recesses corresponding in position to said one pin inserting opening, said terminal portion of each said terminal contact being disposed in one of said plurality of radial grooves. 